Short-circuiting device for electrolytic cell



Feb. 10, 1970 DRUYLANTS SHORT-CIRCUITING DEVICE FOR ELECTROLYTIC CELL' Filed Oct. 4, 1966 2 Sheets-Sheet l Feb. 10,1970 P DRUYL-ANT$ T 3,494,850"

SHORT-CIRCUITINGDEVICE FOR ELEGTRQL'YT'IE CELL Filed not. 4.. I966 2 Sheets-Sheet 2 FIG. 4

United States Patent 3,494,850 SHORT-CIRCUITING DEVICE FOR ELECTROLYTIC CELL Paul Druylants, Woluwe-Saint-Pierre, Brussels, Belgium,

assignor to Solvay & Cie, Brussels, Belgium, a corporation of Belgium Filed Oct. 4, 1966, Ser. No. 584,149 Claims priority, application Netherlands, Oct. 4, 1965, 6512846 Int. Cl. B01k 3/00; C22d 1/04 US. Cl. 204228 6 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a device for short-circuiting an electrolytic cell. The short-circuiting devices of the present invention are particularly adapted for use with mobile mercury cathode cells which electrolyze aqueous solutions of alkali metal halides.

Presently, the devices generally used for short-circuiting mobile mercury cathode cells consist of a set of rapidbreak disconnectors each having a heavy contact connecting it simultaneously to two copper has bars, one of the bus bars being in contact with the sole plate of one cell and the other of the bus bars being in contact with the sole plate of an adjacent cell and the bus bars being of sufiicient thickness to assure the apportionment of the current along the entire length of the sole plates of the two adjacent cells. Such devices are very expensive due to the considerable quantity of copper used.

According to the present invention, it has now been found that it is possible to short-circuit the electrolytic cells by means of disconnecting devices electrically connected directly to the sole plate of the cell and arranged in mutually spaced relation along the entire length of the sole plate. It is found that this arrangement assures a distribution of short-circuit current through the entire length of the sole plate. Moreover, since the sole plate itself acts as a current conductor, the use of bus bars for this purpose is obviated. Finally, the disconnecting devices do not consume any otherwise usable space or act as obstructions because they are positioned under the sole plate, for example, between the stiffening members in the case of a rigid sole plate.

The disconnectors generally used in electrolytic cells require very rapid operation, i.e., operation in a period on the order of hundredths of a second. On the other hand, the apparatus of the present invention allows relatively slow operation, on the order of a second or a few seconds. This slower operation permits the use of control mechanisms and transmission devices which require substantially less power. Accordingly, the foregoing constitutes an additional advantage of the present invention.

According to the invention, the short-circuiting of an electrolytic cell of a serially electrically connected plurality of electrolytic cells is effected by means of a plurality of slow (i.e., on the order of one second or a few seconds) operation disconnectors or switches having electrical contacts, preferably linear tulip contacts,

3,494,850 Patented Feb. 10, 1970 arranged along the length of the cell and electrically connected directly to the sole plate of the cell. The sole plate acts as a conductor electrically interconnecting the contacts. A plurality of electrically conductive mobile or switch members are each arranged in juxtaposition to a respective one of the contacts. Each of the switch members is electrically connected to the sole plate of a next adjacent cell. Finally, there is provided means adapted to move the switch members simultaneously into contact with the contacts in order to short-circuit the cell and then move the switch members back out of contact with the contacts to reestablish operation of the cell. Preferably, the means for moving the switch members comprises members arranged as a plurality of parallelograms each of which is articulated on a set of guide rods. At least one of the switch members is mounted on each of the parallelograms and there is provided means for simultaneously actuating the sets of guide rods thereby to simultaneously move the parallelograms and therewith the switch members.

The invention will now be described in more detail by reference to the drawings, in which:

FIG. 1 is a longitudinal section of the sole plate of a cell provided with the short-circuiting device of the present invention, the disconnectors being in open position;

FIG. 2 is a view corresponding to FIG. 1 but in which the disconnectors are in closed position;

FIG. 3 is a transverse section of two adjacent cells;

FIG. 4 is a detailed transverse section of the shortcircuiting device itself.

The means for simultaneously moving the switch members of the disconnectors comprises a plurality of parallelograms 1 articulated on guide rods 2, 3 and 4 and connected by transmission rods 5 to a control cylinder 6 (FIGS. 1 and 2). The control cylinder 6 is of conventional construction and axially moves the control rods 5 by hydraulic, pneumatic or magnetic actuation, for example. Thus, the cylinder 6 may contain a piston integral with the first of the control rods 5 which piston is driven by means of air or a liquid. Furthermore, the first control rod 5 may be activated in the cylinder 6 electromagnetically. Thus, the cylinder 6, in fact, comprises a pneumatic, hydraulic or electromagnetic control switch.

Attached to a side of each of the parallelograms, which side is defined by a rigid metal strap 14, is a plate 7 carrying a plurality of switch members or knives. Silverplated copper linear tulip contacts having fingers 8 mounted in direct electrical contact with the underside of a sole plate 13 of an electrolytic cell by means of a copper angle-piece 19 (FIG. 4).

The knives 7 are electrically connected to the sole plate of an adjacent cell by means of flexible copper connections, such as wire, 9 (FIG. 3). When the cell is not short-circuited the current is transmitted to anode 10 of the cell by means of copper bus bars 11.

The guide rods 2, 3 and 4 are articulated at one end to the parallelogram 1 and at the other end to a fixed support frame 12 (FIG. 4).

The pltae 7 carrying the knives is mounted on the strap 14 by means of screws 15 and the plate 7 and the parallelogram 1 are electrically insulated from each other by insulation 16, 17 and 18 (FIG. 4).

For short-circuiting of the cells, the control switch 6 is actuated to move the control rod 5 and the control rods 5 move the parallelograms 1, the guide rods 2, 3 and 4 on which the parallelograms 1 are articulated permitting the movement of the parallelograms 1 (FIG. 2). The knives are thus moved into engagement with the fingers 8 whereby electrical contact is established for the short-circuiting. When it is desired to reestablish operation of the cells, the guide rods 5 are moved back to their original axial position by the control switch 6 whereby the parallelograms 1 are returned to their original position (FIG. 1) and the knives are wtihdrawn from engagement with the fingers 8.

While the invention has been described in detail by reference to a particular embodiment thereof, it is to be understood that this embodiment is intended only to illustrate and not to limit the scope of the invention.

What I claim and desire to secure by Letters Patent is:

1. In a series of movable mercury cathode electrolytic cells each having a sole plate and anodes and means electrically connecting the sole plate of one cell with the anodes of an adjacent cell to electrically connect said cels in series, means for short-circuiting a cell comprising a plurality of knife switches comprising a plurality of aligned tulip contacts on said sole plate, said contacts being arranged along the length of said sole plate and being fastened directly thereto and in electrically conductive relation therewith, and movable knives engageable with said contacts, flexible coupling means electrically connecting said knives with the sole plate of an adjacent cell, parallelogram means for moving said knives into and out of engagement with said contacts, means interconnecting said parallelogram means of said knife switches of a cell for simultaneous operation, and means for actuating all of said parallelogram means simultaneously.

2. Apparatus according to claim 1, in which said parallelogram means comprises parallel pairs of pivotally interconnected toggle-action levers, frame means pivotally supporting one lever of each pair and means pivotally connecting the other lever of each pair with said knife.

3. Apparatus according to claim 1, comprising a link pivotally connected at one end to said knife and extending approximately perpendicular to the direction of movement of said knife and in its plane of movement and frame means pivotally supporting the other end of said link to .guide said knife in its movement.

4. Apparatus according to claim 2, in which said interconnecting means comprises link means interconnecting said toggle-action levers of said disconnecting switches of said cell.

5. Apparatus according to claim 4, in which said actuating means comprises a fluid pressure motor connected with said interconnecting means.

6. Apparatus according to claim 1, in which said actuating means has an operating time .of the order of a second to a few seconds.

References Cited UNITED STATES PATENTS 2,443,112 6/1948 Morin 204267 2,508,523 5/1950 Krebs 204231 XR 2,834,728 5/1958 Gallone 204228 XR JOHN H. MACK, Primary Examiner D. R. VALENTINE, Assistant Examiner US. Cl. X.R. 204250, 267 

